Charles leon libby



2 sheets-snet 1. G. L. LIBBYl (No Model.)

, www um @REW mms. No. 442,230.

Patented Dea. 9, 1890.

A @Zwcw CmrZeZeon .Zi

UNITED STATES PATENT. OFFICE..

. CHARLES LEON LIBBY, .OF BRIDGEPORT, CONNECTICUT, ASSIGNORLTO EDWARD P.BULLARD, OF SAME PLACE.

CHUCK FOR SCREW-MACHIN ES.

SPECIFICATION forming part of Letters Pate'ntrNo. 442,230, datedDecember 9, v1890. Application filed August 16, 1890. Serial Nol362,190. (No model.)

To aZZ whom it may concern 'Y Be it known that 1CHARLES LEON LIBBY, acitizen of the United States, residing at l-ridgeport, in the county ofFairfield and State of' Connecticut, have invented certain new anduseful Improvements in Chucks for Screw-lilachines; and l do herebydeclare the following to bea full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

'llus inventioli relates to certain new and useful improvements inchucks such as are used in screw-machines and similar machines, and hasfor its object to provide a chuck in which a parallel movement isimparted to two independent graspingsurfaces, whereby the rod to beworked is held perfectly axial with the chuck, and, furthermore, it isthe object of my invention to provide simple and eicient mechanismwhereby the appropriate movement of the chuck, both opening and closing,may be edected; and with these ends in view my invention consists in theconstruction and the several combinations of co operative elementshereinafter to be fully and in detail explained, and then recited, inthe claims.

In order thatthose skilled in the art to l which my invention appertainsmay fully understand both its construction and its method of operation,I will proceed to describe them 1n detail, reference being had to theaccompanying drawings, which form a part of this specification, and inwhich- Figure 1 is the front elevation, partly in section, and Fig. 2 acentral vertical longitudinal section. v f

Like numerals denote the same parts in both the figures of the drawings.

y The standard, which is designated by 1, is mounted upon the bed of thelathe,-which I have not. thought it necessary to show, as is common andusual inpsuch machines. The lower end of said standard is provided witha bearing,in which is journaled and adapted to revolve a hollowlathe-spindle 2. The forward end of this spindle carries an annulaiheadWithin the extreme outer end of this head is firmly secured a ring 4,whose sectional shape is shown at Fig. 2, and whose interior istherefore tapering. Somewhat behind this ring is a second ring 5, verysimilar iu shape, but oppositely tapered, and so arranged within thebore of the head that it may have a sliding movement therein toward andway from the ring 4, for the purpose presently. to be explained.

6 is a sleeve having either end thereof. l At itsl center itisucut awayboth within and without,althoughrlthis; x' is not absolutely essential.Saidring issplit 'j from bothends, as shown at 8, Fig. 2, theslitsgraspingsurfaces 7 at therein being cut alternately from each exftremity. Said ring has kalsovupon each endff y' tapered surfaces 9,which, when the chuck is in the central position are adjacent to thetapered surfaces of the rings 4 and 5.

From the foregoing description and an inspection of Fig. 2 of thedrawings it is appar-v ent that if therring 5 be forced toward the riug4the action of the two rings will be to compress the split sleeve, whichis enabled by the slit therein to yield inwardly.

. The second portion of my invention has for its object, as heretoforestated, a means for operating the parts hereinbefore described, and" themechanism which I employ for this purpose is as follows: Upon opposite-sides I cut through the head 3 recesses l0, in each ofv which I pivot alever 11, having a short projection 12, which abuts against the rear endof the ring 5, and a longer projection ort-ail 13. EitherI two or moreof these levers may.

be used, as convenience may dictate; but two vare amply suflicient forall practical purposes.

Arranged around the outside of the head isa ring 14, having a groove 15in its outer surf e face, and being recessed, as shown at 16, lto formhousings, in which rest rolls 17, imme. diately over and in contact withthe parts 13 of the levers 11. This ring 14 is adapted to have a slidingmovement lengthwise ofv the v head for the purpose of changing thebearing between the rolls and levers, as presently to be set forth. Ayoke 18 partially embraces the ring 14, resting iu the groove 15. Thisyoke is fastened to or made integral with a 1 sleeve 19, which isarranged tolslide upon'a shaft 20, which latter extends horizont-ally,as I;

shown in Fig. 2, and has no movement. I

21 is a gear, which is journaled in an ex- (No Model.) 4 sneezesheen 1.

G.'SEYBOLD. BOOK TRIMMING MAGHINB. No.1442,295. Patented DemQ, 1890.

Q! QL am I l

